what happens to the potential energy of a capacitor when its plates are moved apart?

Answer 1

Work has to be done against an attractive force tending to bring the plates together. The effect this work has on the system is to cause an increase in (electric) potential energy. It is just reasonable for this to be so, because as the plates are pulled apart, an electric field is set up in a region of space where previously there were none -at least, if we neglect fringe effects.

If there's a dielectric between the plates, it remains charged even if the capacitor is completely dissasembled. Most of the energy involved is thus stored in the dielectric as an electric field.

If the capacitor is reassembled -assuming the armatures weren't previously discharged- the attracting force will be capable of doing work, just the same amount required to disassemble it. The electric energy stored will remain the same as it was before disassembly.

Answer 2

The voltage increases as the plates are separated. The potential energy goes up to.
The same number of electrons (or holes) is present; the field generated is based on the dielectric and the distance between the plates and is described as volts per unit distance. As the distance goes up the total voltage goes up. Work is converted into electrical energy directly (no magnetism).
This is the same principle that applies to Van DeGraff machines. A small charge of static electricity is generated and the charge moved away by the moving belt, thus the voltage is increased.
The same principle applies in thunderstorms, small charges are pulled apart by winds and lightning is generated.

Answer 3

when the plates of a capacitor are moved apart, then the energy stored increase. see,if u move the plates apart, u have to do some work against the attractive force between the capacitors. where will this work done go? this will be stored in between the plates.

Capacitance and hence energy stored is inversely proportional to the distance between the plates, thus increasing the plate separation will decrease the capacitance and consequently decrease the energy stored by the plates.

Answer 4

Hmm, lessee, a cap stores 0.5CV^2 joules, and C is proportional to plate separation, so clearly C will decrease (V should not change, I guess) and therefore the potential energy.

I dunno. Damn good question, I'm going to check back later even if I can't find the answer just to see if anybody comes up with a good answer. Besto'luck-

Oh!!!!! I got it! Since the force is based on electrostatic attraction, it was dissipated as heat in resisting the mechanical force that separated them? Gotta be something close to that........